Graduation puzzles

byaleconJune 27, 2006

I’ve got a couple of graduations to attend over the next few days. It’s the season, you know.

Anyway, at the moment I am sitting in the ceremony for Rideau Valley Middle School, where they’re calling the graduates to the stage. Being mathematically minded, I’ve noted that the classes are numbered 8-1, 8-2, 8-4, 8-6, and 8-8. It’s not a geometric sequence, nor is it a fibonacci sequence. What’s the algorithm to generate this sequence?